Impact device



1.. KfoAvl s IMPACT DEVICE Feb. 11, 1936.

Filed Sept. 25, 1931 INVENTOR BY 1/9 'ATTORNEYS Patented Feb. 11, 1936UNITED STATES IMPACT DEVICE Lewis K. Davis, Hampton, N. J.

Application September 6 Claims.

means of rapidly expanding gases of combustion has been utilizedheretofore for various purposes, but unless the rate of expansion ofthegases is controlled in some way to insure complete combustion of thematerial before utilizing the force thus generated, the maximum power ofthe gas expansion is not obtained, for the reason that the resistance tomovement of the object to be moved is usually relatively low as comparedto initial power provided by the partial combustion of the material, sothat the reserve power of the remaining unburned material is dissipatedin the enlarged space provided by the premature movement of the object.

It is the principal object of this invention to provide a device inwhich the expansion of gases produced by the rapid combustion of ahighly combustible material is retarded a suflicient time to permit ofcomplete combustion of the material whereby the full power of theexpanding gases may be utilized to do a greatly increased amount ofwork. i I

, This object is obtained in a preferred embodiment of the invention inwhich a cartridge of gunpowder or the like is detonated in a cylindercontainingfa piston, whose movement is retarded bynovel means until thepowder is completely burned and the resultant gas pressure exceeds alimit determined by the retarding means. More particularly, theretarding means comprises a bar or rod of metal or the like which issheared off by the piston only when the gas pressure builds'up to apressure such that the shearing resistance of the rod or bar isexceeded. Thus, ,the

impact of the piston caused by the sudden re-' lease thereof by theshearing of the rod or bar is utilized to do useful work such aspunching,

die-pressing or forming metals, pressingtwo or more members together, orthe like, and the frame of the device is arranged for receiving dies ofdifferent shapes punches of different sizes and shapes and the like forcooperation with the piston. I

By changing the density or character of the powder in the cartridges andproviding bars or rods of different shear resistances, any degree ofcontrolled power or force may be obtained with the new deviceof thisinvention, depending upon requirements.

It will be seen that the new impact press of 23, 1931', Serial No.564,491

this invention is compact and readily operated without ,the use ofoutside power, and requires only a supply of powder cartridges and shearrods for procuring repeated operations of the device. Accordingly, thedevice may be used in outlying districts where power is not readilyobtainable and is also admirably adapted as a portable source of power.For a better understanding of the invention, reference is made to theaccompanying drawing, in which Fig. 1 is a longitudinal section throughthe new press as seen along line l-l of Fig. 2;

Fig. 2 is a longitudinal section through the new press as seen along theline 2- -2 of Fig. 1;

Fig. 3 is a transverse cross-section through the cartridge firingmechanism as seen along the line 33 of Fig. 2;

Fig. 4 is a transverse cross-section through the cylinder and piston asseen along the line 4-4 of Fig. l, and

Fig. 5 is a transverse cross-section through the die holder as seenalong the line 5--5 of Fig. 1. In the drawing, numeral I0 designates theframe of the press which is supported on four feet II and is providedwith a die or other tool chamber l2 at the base with which communicatesthe lower end of the power cylinder l0 extend ing upwardly from theframe It.

The head of the cylinder I0 is provided with a lateral recess iii inwhich is removably mounted a block it having a pin l5 extendinglaterally through the head of the cylinder l0 and having a notch H whichis normally engaged by one end of a latch I6. This latch I6 is pivotedon a stud I8 screwed into the side of the head of cylinder l0.

Slidably mounted in an axial passage through the block it is a firingpin l9 which is normally urged in a downward direction by a coil spring20 seated between a collar l9 on the firing pin l9 and thecap 2|threaded on the upper end of block 14. The firing pin I9 is normallyheld in retracted position by the locking pin 22' which is insertedthrough a suitable opening in the firing pin 19 and overlies the cap 2|.In this way the spring is compressed in readiness for advancing thefiring pin l9 when it is released by withdrawing locking pin 22". Ahandle 22 on the firing pin l9 may be pulled outwardly toretracttheflring' pinand for the purpose of inserting the locking pin 22' tohold the firing pin [9 in re- .tracted position; Any other equivalenttrigger or firing pin'release mechanism may be employed with equalfacility.

The upper end of the cylinder I8 is closed gas tightly by a plug orcartridge clip 23 having an axial passage for the reception of thecartridge 25 containing gunpowder, or the like. The percussion cap 26 ofthe cartridge 25 lies in alignment with the tip 21 of the firing pin I 9so as to be struck and detonated thereby when the pin is released. Thecartridge clip or-plug 23 may be exposed for removing empty cartridgeshells and replacing them with unfired cartridges by removing block Hi.This may be done by releasing latch Hi and withdrawing the block fromthe recess l3 in the head of the cylinder Hi. It will be observed in thesection of Figs. 1 and 2 and in cross-section of the block illustratedin Fig. 3 that the head of cylinder I0 is formed with flanges I3 whichoverlap the block l4 so that it is locked against the recoil shockproduced by the firing of cartridge 25.

Slidably mounted in the bore of cylinder I0 is a. piston 28 whose upperend lies adjacent the lower or discharge end of the cartridge 25 whenthe piston lies in the raised position illustrated in Figs. 1 and 2. Thelower end of this piston 28 is provided with an enlarged hammer 29having side grooves adapted to receive the keys or guides 38 on theframe I0. Passing laterally through the piston 28 is a hardened steelbushing 3|,

which is adapted to align with similar hardened steel bushings 32 and 33inserted in the opposite side walls of frame If! when the piston 28 andits hammer 29 are raised into the position shown in Figs. 1 and 2. Thepiston 28 and its hammer 29 may be so raised by means of suitable leversor the like inserted in recesses 34 in thesides so as to hold the piston28 and its hammer 29 in raised position, is a rod 35 of tough metal orthe like having a predetermined resistance to shearing by the shearblades 32' and 33'. Secured to the ends of a small shaft 36 journalledin frame ID are a pair of clips 31 and 38, clip 38 being provided with alateral handle 39, whereby both clips may be raised from their normalposition in which their free ends cover the open ends of bushings 32 and33. The stop pin 38 locates these clips 31 and 38 in this normalposition in which they hold in place the shear rod 35. When it isdesired to remove the severed pieces of the sheared rod and replace itwith a new rod, it is only necessary to grasp handle 39 to move clips 31and 38 to expose the openings in bushings 33 and 32 respectively.

Located in the bottom of the die opening l2 .of frame I0 is acombination anvil and. die 40, whose lower edge is provided with agroove through which passes the bolt 4|, this bolt acting as a key forcentering the anvil die 48 and also serving to clamp it securely in theframe by drawing together the two sides of the frame as the bolt 48 istightened.

Slidably mounted in the opening of the frame and centered and guided bythe keys is the upper die 42 which cooperates with the lower die 40 inthe usual way. These dies 49 and 42 may be shaped to produce any kind offorming operation, punching operation, shearing operation, or the like.For example, as shown in the drawing, the dies 49 and 42 are shaped toembrace a sheath 43 which is adapted to be clamped around the cable 44.Although the dies are shaped in this way to perform this cable sheathingfunction, they may obviously be arranged and adapted to perform anyother function, or they may be substituted by other mechanical elementswhich are designed to produce work in accordance with the power which isapplied thereto. In order to remove these dies the lower one, 48, israised to clear the bolt 4| and may then be withdrawn, while the upperdie 42 then drops down to clear keys or guides 38 and may also bewithdrawn.

In operation, the piston 28 and hammer 29 are raisedby inserting a leveror rod in recesses 34 in the hammer 29 and a shearing pin or rod isinserted through aligned bushings 3|, 32 and 33 in order to hold thepiston 28 and hammer 29 in this elevated position. Then the clips 31 and38 are moved downwardly to stop 38' by handle 39 to close the open endsof bushings 32 and 33, so that the shear rod 35 is held in position.

The block I4 is removed from the frame 18 after being unlatched byreleasing latch l5, and cartridge 25, containing a charge of gunpowderor other highly inflammable orexplosive mate-- The withdrawal of pin 22'releases firing pinl9 so that spring 20 forces firing pin tip 21 againstthe cap 25 of cartridge 25 to fire the same. The rapidly expanding gasesof combustion of the powder in cartridge 25 tend to force the piston 28downwardly at once, but the piston is retarded by shear rod 35, untilthe gas pressure is suflicient to cause the shear blades 32' and 33' tocut relatively slowly through the shear pin 35. This retardation enablesthe powder to burn completely so that the gases of combustion have fulltime to exert their greatest force before being released. Accordingly,when blades 32' and 33' finally sever the shear pin 35 the hammer 29 isreleased suddenly and is forced downwardly I into contact with die 42with a considerable impact, so that the sheath 43 is instantly clampedaround the cable 44 through the cooperation of dies 40 and 42.

It will be seen that the use of the shear rod 35 prevents prematuremovement of the hammer 25 in response to the initial expansion of thepartially burned powder, and allows sumcient time for completecombustion so that the expanding gases exert their greatest accumulatedforce upon the piston 28 before the hammer 29 is released to strike thedies 42. The relatively slow shear of the rod 35 allows the gas toexpand slightly and thus its power is increased before it is released.Thus by this arrangement a greatly augmented power is procured forforcing the two dies 42 and 48 together.

By providing shear rods 35 of different shearing resistances, the timeof powder combustion and gas expansion may be increased or decreasedwithin limits in accordance with operating requirements. Also, byarranging the density or character of the powder charge in cartridge 25,the speed of powder combustion may be arranged 2,030,080 to suit allrequirements of operation. For example, by increasing the charge incartridge 25 and providing 1 a rod 35 having a high shear modulus apractically unlimited amount of power may be obtained in a simplefashion and without requiring large or extensive equipment or the use ofoutside power.

'I'his'invention may therefore be in outlying districts or other placeswhere power is not obtainable, or in such localities where standard-.ized jobs of forming, shearing, punching or the like are doneoccasionally, and the like. The only supplies necessary to operate thedevice of this invention comprise a number of cartridges 2! of the sameor different strengths, and a corresponding number of shear rods 35 ofthe same or different shear resistances. Thus, simply by replacing thecartridges 25 as exploded and rods 35 as sheared, the device may beemployed any number of times without requiring the use of extensivepower equipment or other outside power supply. Also thedeyice may be setup in a short .time and operated instantaneously and readily ceiving acharge of combustible material for gencrating gas to act on said pistonand move the same, anda shearable member extending be-' tween the frameand the piston for resisting relative' movement between them, saidmember being arranged to be sheared at a predetermined gas pressure.

3. In an impact press, the combination of a frame, a piston slidabletherein, means for receiving a charge of combustible material forgenerating gas to act on said piston and move the same, shearing bladesbetween said piston and said frame, and a shearable member cooperatingwith said blades for severance thereby at a predetermined gas pressure.

4. In an impact press, the combination of a frame, a piston slidabletherein. means for receiving a charge of combustible material forgenerating gas to act on said piston and move the same, said piston andframe having aligned apertures, and a shearable member in the aperturesfor severance by movement by said piston under a predetermined gaspressure.

5. In an impact press, the combination of a frame, a piston slidabletherein, means for receiving a charge of combustible material forgenerating gas to act on said piston and move the same, said piston andframe having aligned apertures, a shearable member in the apertures forretarding movement of said piston, and shearing blades between saidpiston and frame cooperating with said member for severance thereby at apredetermined gas pressure.

6. In an impact press, the combination of a frame having a cylinder, apiston slidable therein, a hammer on the piston, means in the frame forcooperation with said hammer, means for receiving a replaceablecartridge of combustible material arranged to discharge gas into saidcylinder and having a detonating cap, firing mechanism mounted on saidframe for detonating the cap of said cartridge, said mechanism beingmovable to expose said cartridge, a shearable member extending betweensaid piston and said frame, and blades between said piston and frame forshearing said member at a predetermined gas pressure to release saidhammer for impact with said first means.

LEWIS K. DAVIS.

